NOTIFY CUSTOMER THAT HE/SHE MISSED MEETING: MODERATE TONE, REQUEST TO RESCHEDULE
I’m sorry your were not able to make it to our [DATE & TIME, ex. Wednesday, 2:30 PM] meeting. Although I do understand that it is difficult to maintain your busy schedule, in the future, I would greatly appreciate you to notify me of cancellations in advance.
Unfortunately, I believe our meeting would have proven quite favorable to you; [GIVE EXAMPLE OF WHAT CUSTOMER MISSED, ex. I spoke with our lead programmer, who informed me of a way our new order requisition module could save your firm a significant amount of money].
If you are still interested, call me at XXX-XX-XX. I will be happy to schedule another meeting.